1) If you delete the local content IN the old PC, the save will remain there (at least it happens with the demo). It seems that Steam won't delete any file that was not downloaded by the client.

2) Saves do NOT transfer automatically between PCs because Recettear does not support Steam cloud saves. You have to manually backup your saves from the old PC and place them in the new computer (use a USB stick for this).

You can also hook up your old HD and copy all the steam files. See here for details. This way you have your old data (except for the games that use windows' User folders) and don't have to download the games again.

i know because i could continue with my old save i had from an other account hahaha

Nope, saves are in %PROGRAMFILES%/Steam/SteamApps/common/Recettear/save.dat (and its backup, _save.dat).

Some games are well behaved and store savegames and config into your user profile dir (for someone called "YourMom" that would be C:/Users/YourMom/Application Data/Your Game Here on Windows, /home/YourMom/.local/share/YourGameHere on Linux, and I don't know what the hell Mac does nowadays, but should be something very similar to Linux). Sadly some coders are still stuck in stone age and keep writting stuff to their install dirs. Unfortunately, EGS is one of many devs from that large group.